Method of and material for making drawings and other records



UNITED STATES PATENT OFFICE.

CHARLES H. LITTLE, 0F CLEVELAND, OHIO.

METHOD OF AND MATERIAL FOR MAKING DRAWING-S AND OTHER RECORDS.

No Drawing.

To all whom it may concern:

Be it known that I, CHARLES H. LITTLE, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Methods of and Materials for Making Drawings and Other Records, of which the following 1s a full, clear, and exact description.

This invention relates to a method of making drawings and other graphic records which may be employed in the usual way for the production of good copies by the blue print process, and in another aspect the invention relates to drafting materials which are utilized in making the drawlngs or in carrying out the method.

One of the principal objects of the invention is to provide a process or method by which good blue prints can be obtained from original pencil drawmgs, and thus eliminate the necessity of making ink tracings. Still further, the invention aims to provide a method such that good blue prints can be obtained from drawings made from an ink or fluid which does not carry coloring matter in suspension, and therefore does not clog the pen and which can be applied by rubber stamp, thus enabling borders, titles and the like to be stamped on the drawing. Another object is to attain the above mentioned results by a method and by drafting or writing materials having character istics such that the drawing or other record may be changed by making erasures and redrawing over theerased portion or 'portions'if desired. In fact, it is one of the very important features of the invention, particularly if applied to drafting room use, that erasures may be made whenever de sired, not only once, but repeatedly, without injuring the paper or fabric or adversely affecting the blue printing qualities of the latter, and irrespective of whether the lines or characters are in the nature of ordinary pencil lines, or whether they have been chemically changed in the manner hereinafter explained, so as to render them intense and substantially opaque to actinic rays.

Additional objects which will appear from the detailed description are attained by my invention, which may be briefly summarized as consisting in certain novel steps of an improved method of making drawings Specification of Letters Patent.

Patented June 22, 1920.

Application filed June Q, 1916. Serial No. 101,633.

and otherrecords suitable for commercial blue printing, and in certain novel features and characteristics of the drafting materlalsutilized in carrying out the method.

In practising myimproved method the drawing or other record is made on a paper, cloth or other suitable base which is translucent, the drawing or record being made by a pencil or with a fluid used as an ink, or by any other suitable device or by other means hereinafter referred to, and by chemical action the ord are rendered adaptable formaking commercial blue prints. Preferably suitable chemicals which are brought together either at the time the drawing or record is made or subsequent to the making of the drawing or tensity of the ines or markings and renders the latter permanently substantially opaque to actinic rays.

This method may be carried out in many specifically different ways, and the drafting materials which are utilized in practising the method may be modified in many respects, and these will be referred to below, the preferred form of the method and the preferred drafting materials being first explained.

- In practising the method I may utilize a suitable paper, parchment or cloth, and in fact, any base sheet having characteristics which adapt it for drawing or writing and blue printing purposes, and especially for drafting room use. For example, I may use bond paper, tracing cloth, or other thin translucent base or base sheet which is permanent in form, flexible so that it can be readily rolled, and thin. The base sheet is preferably provided with a thin translucent coating, preferably a kaolinic coating, which is composed principally of kaolin, a suitable light pigment, a suitable binder, and a chemical to be referred to presentl This coating is hard and adheres strongl y to the base sheet so that it will not chip, break or crumble or be displaced by pressure. Furthermore, it may be readily scraped or cut from the fibrous sheet beneath for erasure purposes. The coating, which is preferably about .001 of an inch in thickness, is applied to the sheet evenly and uniformly by a spray, brush,.or other suitable means. 7 Additionally, the base sheet is preferably oiled, waxed or gummed so as to increase the translucency of the sheet, and to prevent the coloring matter of the lines or markings penetrating into the fibers of the sheet. The oiling, waxing or gumming may be done before the coating is applied, as is preferred, or after the application of the coating.

One of the chemicals which is utilized in producing the chemical change necessary to 'ender the lines or markings substantially opaque to actinic rays is preferably incorporated in this coating or directly in the fibrous sheet if the coating is not employed. Preferably this chemical consists of gallic acid, which, if incorporated in the coating,

is mixed with the materials from which the coating is made, about 10 per cent. by weight of the gallic acid being used in the coating.

While the coating above explained is preferably utilized and although the chemical is, as before stated, by preference embodied in this coating in order that the drawing or record may be readily erasable after as well i as before the chemical change takes place, the coating may be omitted, particularly if the paper is to be used for certain purposes, in which event the gallic acid or other chemi-' cal will be embodied directly in the paper or other base sheet. This can be done by making a solution containing the proper amount of the chemical, say approximately ten per cent., and impregnating the base sheet with the solution, after which the base sheet will be dried and will then be ready for use, or the chemical may be incorporated in the base sheet during the manufacture of the latter, as for example by mixing the chemical in the pulp or fibrous material from which the base sheet is made. It will be apparent that if the coating is not employed and if the chemical is incorporated in the fibrous sheet, the erasures may be made before the chemical action takes place, but can not readily be made after the chemical action, due to the fact that the coloring matter formed by the chemical action will in the absence of the coating sink into the fibers of the sheet in very much the same way that writing ink sinks into the fibers of ordinary drawing paper or tracing cloth. hen, however, the chemical is incorporated in the coating, if it is desired to make an erasure, even after the chemical action takes place, this can be done by scraping the chemically affected part from the coating, and the erased portion of the paper or cloth can be rewritten or drawn over again. This can be done repeatedly if desired without tearing or marring the fibers of the base sheet and without 'lfecting the blue printing qualities of the latter, particularly it reasonable care is exercised in making the erasures.

In making the drawings on the base sheet prepared as above explained and containing gallic acid or other chemical, I utilize a marking medium containing preferably the second chemical which coacts with the first named to produce the chemical change necessary to intensify the lines or markings made by the marking medium, so as to render the same sufficiently impervious or opaque to actinic rays that good commercial blue prints may be made. Generally, this marking medium consists of a pencil, very much like the ordinary pencil. I prefer to employ for the second chemical a vanadium, such as sodium vanadate or ammonium vanadate. In producing a pencil about ten per cent. by weight of the chemical is mixed with the graphite or other color ing matter and a vanadate being employed in the event that the marking or drawing composition of the pencil is, after being mixed, subjected to a baking process. If it is not subjected to a baking process the ammonium vanadate may be employed. I have found that a pencil gives very good results when the marking portion consists of, about 10 per cent. of the salt of vanadium, 50 per cent. graphite or aniline or other coloring matter, and 40 per cent. clay. If it is not desired to use a pencil having a baked marking composition, I may use 10 per cent. of the vanadium salt, either sodium vanadate or ammonium vanadate, 50 per cent. coloring matter, such as mentioned above, and 40 per cent. Portland cement for a binder. A very small quantity of wax may be added to the composition in either case, if desired. I prefer to use a vanadium salt such as enumerated above for the reason that even though an extremely small quantity of the chemical is applied to the base sheet in making the drawings, exceedingly good results are obtained. That is to say, when one of the vanadium salts is employed, even though a very minute quantity or amount of the salt is applied to the base sheet by the pencil or other scribing means, there is nevertheless produced in the coating or in the fibrous ma terial of the base sheet (in the event the coating is not employed) such a chemical change that the lines are made exceedingly intense and amply opaque to produce very good blue prints. In drawing the lines or making the writing or other record, there is of necessity a small amount of the chemical applied to the base sheet, particularly as the major portion of the pencil is composed chiefly of other materials, including the coloring matter and the binder, but in spite of the fact that a minute amount of the chemical is applied by the pencil or the marking medium, I have found that with. the use of the vanadium salts previously mentioned a very remarkable chemical change takes place, producing exactly the desired results. 'i

salt of suitable binder, sodium To complete the drawing made in the manner above explained, or to render it suitable for blue printing purposes, the drawing, that is to say, the base sheet containing the drawing, is subjected to moisture to become substantially opaque to actinio rays. The sharpness of the lines is not affected in any way, the effect of the chemical action being to render them extremely intense to transmitted light. 7 I

When the drawing or record is first made with pencil before the chemical change takes place, the lines or markings are very similar to those which are produced with the ordinary pencil on a drawing paper or cloth, and can be readily erased with an ordinary rubber eraser, spun glass brush, or with a cutter. This is a very important feature or characteristic, especially when the method is utilized in a drafting 'room. After the chemical action has taken place, if further erasingis necessary, it may be done with a cutter by simply removing a portion of the coating, as the depth to which the chemical action penetrates is such that the coloring matter does not enter into the fibers of the base sheet. This depth of ponetration is restricted by the oiling, waxingv or gumming previously referred to, and to some extent also by the amount of the chemical employed either in the base sheet or pencil or both. The fact that chemical action does not take place in the fibers of the base sheet when the coating is employed and that the drawings are erasable either before or after the chemical action takes place, renders the invention especially adapted for drafting room use, and for numerous other purposes where erasures or alterations are frequently required. In fact, this feature of the invention alone gives the drawings made with my invention a very decided advantage over drawings which, prior to my invention, have been made with india ink on tracing cloth, for it is a well known fact that when an india ink tracing is erased the tracing cloth is damaged to such an extent that not only is it diflicult to make the drawing over because the ink has a tendency to run and thus produce very ragged lines, but the erasure very materially affects the appearance and effectiveness of the blue print.

Instead of using a pencil, the chemical required to cooperate with that in the paper or base sheet may be applied in other ways or with other forms of writing or scribing .or recording means. For example, the chemical whlch is incorporated in the pencil may bedissolved in a suitable solution and applied in the form of an ink or writing fluid by pen or rubber stamp, and the same results can be obtained. An ordinary writing ink which does not carry coloring matter in suspension may be utilized, in which event a suitable amount of the chemical, say about 10 per cent, will be dissolved in the ink. Or any othersuitable fluid or solvent may be employed. It will be understood that the salt of vanadium when thus dis solved in the writing fluid, is not combined i chemically with any other element or chemicalin the solution, but is free, precisely as when used in solid form in the pencil.

I When the chemical is applied by means of the writing fluid, itis not essential to employ moisture to cause the chemical action necessary to render the lines or marks opaque to actinic rays, for the chemical change takesplace as soon as the chemical is applied.

The fluid or ink containing the dissolved chemical as above described has numerous advantages over ordinary inks used in making drawings and records. For example, it has a very important advantage over ordinary india ink in the respect that it does not contain coloring matter in suspension, and therefore will not clog the pen used in applying the fluid to the base sheet. In fact,

the ink or fluid containing the chemical in 1 solution'may beapplied to the drawing or paper by a fountain pen. Also the shape and style of the pen may be modified to -make it more useful for many purposes such and markings stamped on the base sheet are very intense to transmitted light, and will blue print very effectively. This advantage is of extreme importance to draftsmen, for it is a well known fact that borders, etc., cannot be stamped on drawing paper with india ink, and that all other quick drying inks are unsuitable for blue printing.

My invention may be employed for certain purposes which do not require that the chemical be applied to the base sheet either with pencil or fluid as above described, For example, the chemical instead of being incorporated in a pencil or fluid, may be incorporated in a ribbon or equivalent medium and the characters, lines or writing applied to the sheet by an apparatus such as a typewriter, in which event the chemical will be transferred from the ribbon to the base sheet, and when the base sheet is subsequently treated by subjecting the same to moisture or moisture and heat, such as steam, the chemical thus applied and the chemical in the base sheet coact to render the writing or record substantially opaque to actinic rays as before described.

It is not essential either that the Paper or base sheet have the chemical incorporated either in the fibrous portion or in the coating of the base sheet, for the chemical which coacts with that applied with the pencil, fluid or other scribing means may be supplied after the drawing or other record is made upon the paper or base sheet 1n some other manner, such, for example, as subjecting the base sheet to the action of a liquid or vapor containing the chemical. This could be done by dissolving a suitable quantity of the chemical which in the instance first described was incorporated in the base sheet, in a suitable quantity of water and then by heat evolving a vapor which carries the chemical to the base sheet. I

Instead of applying the chemical in the form of a vapor by heating a solution containing the chemical, substantially the same results can be obtained by subjecting the drawing direct to the action of the solution containing the chemical. This method of carrying out my invention will under ordinary circumstances or for most uses of the invention be less advantageous than the forms first described.

Inasmuch as the edges of pencil lines are not ordinarily as smooth and clean cut as those of ink lines, it may be desirable in some cases to provide on the white translucent coating of the base sheet first described a very thin coating, such as wax, so that the point of the pencil containing the chemical adapted to coact with the chemical in the translucent coating, as previously explained, will cut through or push aside this extra coating, thus making the edges of the lines very smooth and even. By employing a paper or' base sheet covered by a coating, as just described, an ordinary pencil could be employed in making the drawing or record and the line intensifying chemical could be applied in the form of a liquid or vapor, or if desired, the drawing or record could be made by means of a stylus, in which event, it would be desirable that this thin extra coating be given a color which will contrast with the white coating beneath.

After the drawing is made in this fashion with the stylus or other suitable cutting tool, the lines or characters are made substantially opaque to actinic rays by subjecting the sheet to the action of water, steam or vapor containing the chemical which coacts with the chemical in the sheet.

It will, therefore, be seen that my invention in the aspect of the method or process of making drawings and other records suitable for producing commercial blue prints may be carried out in numerous specifically different ways, each containing, however, the basic or important feature of causing the lines or markings to become black and substantially opaque to actinic rays by chemical action, and while I have disclosed and described with considerable detail numerous ways of carrying out this method, it is to be understood that I am not to be confined to any of the precise methods disclosed, as other ways of carrying out the invention may suggest themselves to one skilled in the art. Furthermore, while I have stated the.

particular chemicals which I prefer to employ, I do not wish to be confined to the same, as the same results that I have obtained, or results substantially as effective might be obtained by the use of chemicals that are not herein referred to. I have tried very many different chemicals and combinations of chemicals and those which I have specified have proven to give exceedingly good results, even though small amounts of the chemicals are employed. This is true particularly of the vanadium salt which is preferably incorporated in the marking or drawing medium, as before stated. A further advantage resulting from the use of the chemicals above specified, lies in.

the fact that by the chemical action resultmg from the combination of said chemicals,

-the lines or markings of the drawing or other record, are permanently intensified or are rendered permanently opaque, or substantially opaque to actinic rays. In other words, the chemically intensified lines do not in time fade or undergo a slow chemical change which would render them indistinct, or unsuitable for blue printing purposes.

In the above description and in the introductory part of the specification, I have frequently used the term commercial blue prints. By such an expression, I mean blue prints such as are obtained or made in ordinary drafting rooms from tracing cloth on which drawings have been traced, the results which I have obtained by my invention being substantially the same as that obtained from tracing cloth, but without the expense and labor of tracing the drawings.

Having thus described my invention, what I claim is:

1. The method of making a drawing or other graphic record, which comprises making the drawing or record on a base, and by chemical action rendering the drawn or inscribed lines or markings substantially opaque to actinic rays.

2. The method of making a drawing or other graphic record adapted for commercial blue printing which comprises making the drawing or record on a translucent base and by chemical action rendering the drawn or inscribed linesor markings substantially opaque to actinic rays.

8. The method of making a drawing or other graphic record adapted for commercial blue printing which comprises making a drawing or graphic record on a translucent base containing a chemical which coacts with a chemical applied to the base so as to increase the opaqueness of the lines or markings to actinic rays.

41-. The method of making a drawing or other graphic record adapted for commercial blue printing which comprises making on a base sheet the drawing or record by means of a .marking or scribing medium containing a chemical adapted to coact with another chemical to substantially increase the opaqueness to actinic rays of the lines or markings.

5. The method of making a drawing or other graphic record adapted for commercial. blue printing which comprisesmaking on a base sheet containing a chemical the drawing or graphic record with a marking medium containing a chemical adapted to coact with the first named chemical to cause a chemical action which substantially in creases the opaqueness of the lines or mark ings to actinic rays.

6. The method of making a drawing or other graphic record which comprises making the drawing or graphic record on a base sheet containing a chemical, and subsequently treating the base with the drawing thereon, so as to cause a chemical action which permanently and substantially increases the intensity of the lines or markings to transmitted light.

7. The method of making a drawing or other graphic record capable of being used for making good blue prints which com prises making the drawing or graphic record on a base sheet containing a chemical and subsequently treating the base with the drawing thereon, so as tocause a chemical action which substantially increases the in-' tensity of the lines or markings to transmitted light. 7

8. The method of making a drawing or other graphic record capable of being used for producing commercial blue prints which comprises making on a translucent base containing a chemical the drawing or record by means of a scribing medium containing another chemical and subsequently treating the drawing so as to cause a reaction between the chemical in the base and the chemical applied by the drawing, marking or scribing medium, so as to substantially increase the opaqueness of the lines to actinic rays. a

9. The method of making a drawing or other graphic record capable of being used for making commercial blue prints which comprises making the drawing or record on a translucent base whose scribing surface is in the form of a coating and by chemical action in the coating causing the lines or inscribed matter to become substantially opaque to actinic rays.

10. The method of making a drawing or other graphic record which comprises making the drawing or record on a base having a drawing or scribing surface consisting of a coating containing a chemical, and substantially intensifying chemically the lines or characters to transmitted light.

11. The method of making a drawing or other graphic record capable of being used for making commercial blue prints which comprises making the drawing or record on a base having a drawing surface consisting of a coating containing a chemical, and

by chemical action rendering the drawn or other graphic record suitable for producing commercial blue prints which comprises making by means of a scribing medium containing a chemical, the drawing or graphic record on a translucent base sheet whose marking or drawing surface consists of a coating provided with a chemical which is adapted to coact with the first named chemical to cause the lines or markings of the coating to become substantially opaque to actinic rays.

13. The method of making a drawing or other graphic record suitable for the production of commercial blue prints which comprises making the drawing or graphic record by means of a marking or scribing medium containing a chemical, on a translucent base provided with a drawing or scribing surface in the form of a coating, and subse uently treating the drawing to cause a c emical change in the coating which increases the opaqueness to actinic rays of the lines or markings.

14. The process of making a drawing or other record suitable for commercial blue printing which comprises first making the drawing or record on a translucent base sheet with lines or markings through which actinic rays may pass and subsequently chemically changing the lines or markings so as to render them intense to transmitted light and substantially opaque to actinic rays.

15. The process of making a drawing or other record which comprises making the drawing or record on a base from which the lines or markings may be readily erased, and substantially intensifying chemically the lines or markings to transmitted light.

16. The process of making a drawing or opaqueness and intensity of the lines or markings to transmitted light.

18. The process of making a drawing or other record suitable for commercial blue printing which comprises making the lines or markings on a translucent base with coloring matter in the form of a scribing medium containing a chemical capable of reacting With a second chemical to cause the lines or markings to become substantially opaque to actinic rays. 7

In testimony whereof, I hereunto affix my signature.

CHARLES H. LITTLE. 

